Library /sys$common/syshlp/ncphelp.hlb SET, EXECUTOR, MAXIMUM ADDRESS number  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Indicates the largest node address and, consequently, the greatest
 number of nodes within an area that can be addressed by the local
 node. The default  is 1023.

 If you receive an "invalid value" error, you probably have not
 allocated  enough nonpaged pool space.  You must lower the MAXIMUM
 ADDRESS value or  increase the VMS NPAGEDYN value.  (Use the System
 Generation Utility (SYSGEN) to change the NPAGEDYN parameter.)